A hybrid model for assessing the quality performance of demolition contractors

Abstract

The demolition project is reasonably labour-intensive and the shortage of qualified demolition contractors resulted in poor workmanship in many demolition projects. The current performance assessment of demolition contractors in Malaysia is highly based on subjective evaluation while a few of authorities and clients incorporated contractor past performance within the quality assessment process. This is due to the lack of an assessment framework that can supports the evaluation process of demolition contractors. However, different contractor’s quality assessment methods have been successfully developed, but, there has been limited effort to view complexity parameters in the process of evaluation. Hence, it made it necessary to identify an appropriate assessment criteria in order to evaluate the quality of demolition contractor’s performance in a structured way along with considering the complexity of demolition project. This research first applied the Delphi method as a scientific means to collect the required information for developing of the assessment framework, which constitutes thirty performance indicators for demolition contractors. Then, an assessment method has been developed in the form of a hybrid Quality Function Deployment (QFD) and Cybernetic Analytic Network Process (CANP) model for demolition contractors. This involves the use of QFD to translate the customer’s expectations into assessment indicators and the CANP to weight the expectations and assessment criteria. Three different case studies were used to demonstrate the implementation of the model and the results indicated that despite the extensive consideration on cost and time in the assessment of demolition contractors, the safety indicators were rated as the most significant Malaysian clients’ expectations for quality assessment of demolition contractor. The results also show that, the project complexity indicators, comparatively received high priority in the quality assessment of demolition contractors among all other indicators. In conclusion, this research has demonstrated that the developed hybrid model is an effective tool for assessing the quality of demolition contractor’s performance and it is hoped that the research work may provide a first step into a better customer-driven demolition project, and eventually increase the quality of demolition projects over time.